A Guide on the Usage of Hydrocarbons in Refrigeration Systems

In chemical terms, a hydrocarbon is a naturally occurring basic compound of carbon and hydrogen, and is typically to be found in large crude oil concentrations. The non-toxic hydrocarbons are now widely used as a modern refrigerant, being an eco¬-friendly alternative to ozone damaging CFC/HCFC/HFC fluorocarbons.

The following three main types of hydrocarbons are widely utilised as refrigerants:

Propane R290

Isobutane R600a

Propylene R1270

The installation and maintenance of all refrigeration systems that contain flammable materials like the above should only be carried out by authorised persons who are certified for that kind of work.

The Chemical Properties of Hydrocarbons

Isobutene and propane, the two most utilised hydrocarbons are compatible with materials used in HFCs and standard oils. One significant exception is propene (or propylene) as it is not neoprene compatible. Consequently, with this refrigerant, special O-rings have to be employed.

Environmental Impact

Because they belong to the category of natural refrigerants, hydrocarbons have negligible GWP and zero ODP. Essentially, they are by-products coming from the petrochemical sector.

The Efficiency of Hydrocarbons

Because of their excellent thermodynamic characteristics, hydrocarbons are good and perhaps even superior contrasted against refrigerants of both HCFC and HCF in the majority of applications.

Safety Considerations

Due to their flammability potential, hydrocarbons are the subject of safety legislation and guidelines internationally. All hydrocarbon systems manufacturers must adhere to equipment safety guidelines. The service personnel must comply and understand specified procedures for safe handling.

Strict specifications as well as safety legislation have stressed on the need for leakage-simulation verification and testing when it comes to the sealing of any electrical components near hydrocarbon flows. Additionally, the majority of commercial and domestic appliances like fridges and freezers, and motor compressors are always subject to globally enforced safety directives.

In general, the usage of ignition sources should be avoided inside the application. The majority of hydrocarbons are in fact non-toxic, the main safety concern only emanating from their high flammability. However, hydrocarbons gases are generally heavier than standard air and may displace the air in your lungs.

Typical Usage

The hydrocarbons impact has been felt most in fridge and freezer domestic applications where what is referred to as the 'Greenfreeze' isobutane (R600a) refrigerant is now being widely used on an international scale. Refrigeration in the commercial sector has also followed suit, basically going for propane (R290) in place of ozone-damaging refrigerants, especially in major supermarket systems.

Typical hydrocarbons applications are:

Domestic and commercial refrigerators/freezers

Beer and bottle coolers

Beverage dispensers

Ice cream freezers

Heat pumps

Dehumidifiers

Small air conditioners

Supermarket refrigeration

Cost Implications

The relative hydrocarbons systems cost largely are determined by the application. In light commercial and domestic usage, the cost is comparable to that of HFCs systems. However, in industrial and commercial applications, HCs systems tend to be comparatively more costly because of the need for installing explosion-proof electrical equipment enclosures.

It is very important to remember that hydrocarbons are an extremely highly flammable substance and should be handled with great care. Towards ensuring safety, the applications using hydrocarbon are governed by several regional, national and international regulations and standards. For this reason, you need not be too anxious about the dangers they pose.

Author: Devina Pareen

Devina Pareen is the only child of two doctors, who were originally from Pakistan. She grew up in Bradford but always wanted to escape to the bright lights down South. Devina took a degree in Economics at Bristol University, then worked for a finance company in Bath for 5 years. At the age of 26, she decided to take a gap year to travel across Asia, and never went back to her old career. Devina's photos of her travels became a popular blog in both the UK and Pakistan, which led to her writing travel articles for online journals.

Devina lives in Brighton with her partner Constance and their two house rabbits Gabriel and Marianne. She trys to swim in the sea most days, even if just for 5 minutes. Devina enjoys indulging her creative side with free form crochet and machine embroidery but as there is now no more room for any more cushions in their house, she sometimes sells her colourful makes at charity sales.